Regular Industrial Processing of Bovine Milk Impacts the Integrity and Molecular Composition of Extracellular Vesicles
Regular Industrial Processing of Bovine Milk Impacts the Integrity and Molecular Composition of Extracellular Vesicles
复制标题
DOI：
10.1093/jn/nxab031
复制
发表时间：
2021-03-25
影响因子：
4.2
通讯作者：
Wauben, Marca H. M.
中科院分区：
文献类型：
--
作者：
Kleinjan, Marije;van Herwijnen, Martijn J. C.;Wauben, Marca H. M.
背景：牛乳中含有细胞外囊泡（EVs），它通过选择性结合的生物活性分子调节受体的细胞过程，作为细胞间通讯的介质。由于其中一些EV成分在进化上是保守的，因此商业牛奶中存在的EV可能具有调节人类消费者细胞过程的潜力。目的：由于商品牛奶经过工业加工，我们研究了工业加工对分离的牛奶ev及其生物活性成分的数量和完整性的影响。为此，我们比较了从生牛乳中分离出的ev与从不同类型的商业牛奶中分离出的ev，包括巴氏杀菌牛奶（无论是否均质）和超高温处理（UHT）牛奶。方法：采用差速离心分离ev与其他乳成分，然后进行密度梯度超离心。通过单颗粒高分辨率荧光流式细胞术测定EV数量，冷冻电镜观察EV完整性和形态，western blot分析研究EV相关蛋白，RNA分析评估总小RNA浓度和牛奶EV特异性microRNA表达。结果：UHT乳中未检出完整的EVs。有趣的是,虽然巴氏灭菌法(无论同质化)并不影响意思是+ / - SD EV数字(3.4 x 10 (8) + / - 1.2 x 10 (8) -2.8 x 10 (8) + / - 0.3 x 10(7)与3.1 x 10 (8) + / - 1.2 x 10(8)在原料奶),它影响电动车的完整性和外观,改变蛋白质的签名,导致亏损milk-EV-associated rna(从40.2 + / - 3.4 ng /μL在原料奶17.7 + / - 5.4 - -23.3 + / - 10.0毫克/μL加工过的牛奶,P < 0.05)。结论：通过巴氏灭菌或UHT加热的商品牛奶分别含有较少或没有完整的ev。虽然根据颗粒数，大多数电动汽车似乎对巴氏灭菌有抵抗力，但它们的完整性受到影响，分子组成也发生了改变。因此，在经过热处理的商业牛奶中，生物活性成分通过牛乳电动汽车转移到人类消费者的可能性可能会减少或改变。
Background: Bovine milk contains extracellular vesicles (EVs), which act as mediators of intercellular communication by regulating the recipients' cellular processes via their selectively incorporated bioactive molecules. Because some of these EV components are evolutionarily conserved, EVs present in commercial milk might have the potential to regulate cellular processes in human consumers.Objectives: Because commercial milk is subjected to industrial processing, we investigated its effect on the number and integrity of isolated milk EVs and their bioactive components. For this, we compared EVs isolated from raw bovine milk with EVs isolated from different types of commercial milk, including pasteurized milk, either homogenized or not, and ultra heat treated (UHT) milk.Methods: EVs were separated from other milk components by differential centrifugation, followed by density gradient ultracentrifugation. EVs from different milk types were compared by single-particle high-resolution fluorescence-based flow cytometry to determine EV numbers, Cryo-electron microscopy to visualize EV integrity and morphology, western blot analysis to investigate EV-associated protein cargo, and RNA analysis to assess total small RNA concentration and milk-EV-specific microRNA expression.Results: In UHT milk, we could not detect intact EVs. Interestingly, although pasteurization (irrespective of homogenization) did not affect mean +/- SD EV numbers (3.4 x 10(8) +/- 1.2 x 10(8)-2.8 x 10(8) +/- 0.3 x 10(7) compared with 3.1 x 10(8) +/- 1.2 x 10(8) in raw milk), it affected EV integrity and appearance, altered their protein signature, and resulted in a loss of milk-EV-associated RNAs (from 40.2 +/- 3.4 ng/mu L in raw milk to 17.7 +/- 5.4-23.3 +/- 10.0 mg/mu L in processed milk, P < 0.05).Conclusions: Commercial milk, that has been heated by either pasteurization or UHT, contains fewer or no intact EVs, respectively. Although most EVs seemed resistant to pasteurization based on particle numbers, their integrity was affected and their molecular composition was altered. Thus, the possible transfer of bioactive components via bovine milk EVs to human consumers is likely diminished or altered in heat-treated commercial milk.